Take control. If it seems too good to be true it must be. -- that's senator Claire McCaskill says when it comes to all those ads for quick weight -- trick and helped boosters if only. You take this bill. Drink the shake. Use this device. Americans spend forty billion dollars a year on weight loss products. And today on Capitol Hill for the democratic senator focused on what she says it is false and deceptive advertising for some of them. On the hot seat. Doctor -- -- -- -- thoracic surgeon who became a household name is popular daytime television show focuses on health and wellness issues. Lawmakers noted with they called -- the doctor Oz -- -- When the celebrity doctor mentioned that he pots for example sells for the product rose by 121000%. In the Haskell showed this clip from doctor Oz show -- green -- -- decades and we turned into a supplement. This miracle pill can burn fat fast she's viewers trust doctor eyes. He makes statements like that they pay attention and concern that you are melding medical advice news and entertainment. In a way that harms consumers but doctor rod insists he does not endorse any products nor does he receive any money -- the ones that appear on the show I don't sell anything. They see my name my picture and part of the show Bob an advertisement do not buy the product. The government is cracking down last month the FDC said it is suing the pure green coffee company. For making false weight loss claims after that big boost from doctor arrives. Karen -- ABC news Washington.

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